Filling apparatus



Dec. 13, 1955 N. v. BURDIN FILLING APPARATUS Filed Dec. 1, 1952 lNVEN-TOR:

Nelson Vincenl' Burdin,

Luz/ My i W ATTORNEYS FILLING APPARATUS Nelson V. Burdin, Taplow, England, assignor to Imperial Chemical Industries Limited, a corporation of Great Britain Application December 1, 1952, Serial No. 323,476

Claims priority, application Great Britain:

December 7, 1951 2 Claims. (Cl. 226-124) This invention relates to displacement filling apparatus suitable for use with viscous liquids.

When it is required to fill a series of containers e. g. milk bottles with a predetermined quantity of liquid filling apparatus of the displacement type is commonly used. In the general mode of operation of such apparatus the open end of the container to be filled is pressed against a device which forms an air-tight seal around the top rim of the container, the device being provided with a liquid delivery inlet and an air vent. A valve in the inlet is then opened, liquid flows into the container from a bulk supply situated at a higher level and the displaced air passes out through the vent which usually takes the form of a tube extending upwardly at least as high as the level of the bulk supply of liquid. When the level of the liquid in the container reaches the bottom of the vent tube, the remainder of the air in the container is then trapped and the liquid itself is forced up the tube to the level of the bulk supply. When this stage is reached no more air can escape from the container, and so no more liquid can flow into it. The valve in the inlet is then closed, the air tight seal is broken and the liquid in the vent tube is allowed to drain back into the container.

In this manner a series of containers may be filled to a substantially constant level which is controlled in effect by the height of the bottom of the vent tube. When the container is unsealed liquid drains back from the vent tube, the actual quantity depending on the bore of the tube and on the level of the bulk supply. If the tube is of narrow bore' its total liquid capacity will be small and any small variations in the level of the bulk supply will introduce no significant variations in the total quantity of liquid in the container. This type of apparatus is widely used for filling out mobile liquids such as milk with which vent tubes of about 3 4 inch diameter are satisfactory, but difiiculties arise when it is applied to viscous liquids such as paint. The narrow bore vent tube must be drained at each operation to prevent the possibility of air locks but viscous liquids take a long time to drain from such a tube. If the vent tube is made Wider its liquid capacity increases and the drainage may then introduce significant variation in the quantity of liquid in the container.

The present invention provides a displacement filling apparatus for use with viscous liquids characterised in that the air vent tube is provided with a valve situated at or near its lower extremity and with valve operating means adapted to open the air vent tube valve prior to the liquid inlet valve being opened and to close the air vent tube valve before the filled container is moved relative to the air vent tube, the air vent tube, valve and valve operating means being of such dimensions that air may be vented up the tube even when it contains viscous liquid.

As a result of providing a valve in the air vent tube and closing it before moving the full container, the liquid displaced into the air vent tube is prevented from draiu ing back into and producing variations in the level of the liquid in the full container. Any liquid which drains from the air vent tube does so into the container usedat the next filling and further, the draining can take place only before the liquid in that container has reached the level determined by the bottom of the vent tube. When this level is reached no additional liquid can enter the container and the air vent tube is closed to prevent further drainage when the container is moved. As a result of this method of controlling the drain back it is possible to make the air vent tube, valve and valve operating means of such dimensions that air may be vented through the tube even when the tube contains liquid. A further advantage which then arises is that with such a tube and valve arrangement it is not necessary to completely drain the tube before carrying out the next filling operation. It is only necessary to open the air vent tube valve before the liquid inlet valve in order to ensure that the head of liquid in the air vent tube is less than that of the bulk supply to the liquid inlet. Although the liquid inlet valve should not be opened until the container is sealed, the air vent valve may be opened either before or after sealing takes place. In a preferred form of the invention the air vent valve is opened before the container is sealed since drainage then takes place more quickly.

One form of the invention will now be described by way of example with reference to the accompanying drawing which shows a section of a displacement filling apparatus with a container in the filling position. A container 1 for the bulk liquid is provided with a sump 2 at the bottom of which are valve orifices 3 and 4. The orifices 3 and 4 may be closed by valve heads 5 and 6 which are operated by a cross beam 7 and a downwardly extending connecting 'rod 8. From orifice 4 there extends upwardly through the bulk supply container 1 an air vent tube 9. The cross beam 7 is free to move vertically up and down and is guided by rod 10 which runs in guides plates 11 attached to the vent tube 9. The sump 2 is provided externally with a spring loaded collar 12 and a retaining circular retaining clip 13. Loosely mounted on the collar by means of pins 14 located in grooves 15 is a sealing ring which is provided with a resilient gasket 17. In the inoperative position the collar 12 is in contact with circular retaining clip 13 and the sealing ring 16 is suspended by pins 14. To operate the apparatus a container 18 is placed beneath the sealing ring 16 and then pushed upwards by a base platform (not shown). The rim of the container first makes contact with the gasket 17 and then lifts the sealing ring 16 until it contacts the connecting rod 8. As the ring continues to rise it lifts the rod 8 and the cross beam 7 and opens the air vent valve 6, thus allowing any liquid in the air vent tube to drain into the container. The gasket then makes contact with the spring loaded collar 12 and further upward motion of the container compresses the collar spring and ensures that the resilient gasket forms air-tight seals between the container and the collar. Continued upward motion of the container now lifts the connecting rod 8 and attached cross beam 7 to the upper limit of the slot 19 in the stem of the liquid supply valve 5 and finally this latter valve is lifted. This is the position shown in the drawing.

In the period between the opening of the two valves, liquid left in the vent tube from the previous operation begins to drain into the container and when the liquid supply valve is opened liquid flows in from the bulk container and displaces air through the vent tube. Even partial drainage of the vent tube is sufficient to prevent an air lock since the bore is made wide enough to permit air to escape through liquid in the tube. When Patented Dec. 13, 19556 the level of the liquid in the container reaches the bottom of the .vent' tube, the remainder. of the. air in the container, is trapped and the, vent tube then fills with liquid. Owing to the air-tight'seals formed by the gasket 17' no more air can escape from thecontainer l8 and so thefiow of liquid. from the bulk supply container- 1 ceases. a

The connecting rod 8 is now knocked; awayfrom the sealing ring 16 and the valves 5 and 6 drop back On lowering the container 18,- theonto their seats. v I 7 spring loaded collar lz pu'shes the sealing ring'lfi downwards until the motion of the collar- 12 is arrested by the circular retaining clip 13, the air-tight gasket'seals are :broken and the downward motion of the sealing ring 16 is finally arrested by the pins 14. J a v The dimensionsof the air vent tube, valveand valve operating means which will allow air tobe vented even when the tube contains liquid will depend on the viscosity,

of the liquid being filled out. 'For use with paint it has been found that a tube of approximately one'inch diameter, a valve of approximately /8 inch diameter and valve operating means of a smaller diameter are suitable.

These dimensions apply when, as in theapparatus de- 7 scribed above, the valve head is withdrawn into the vent tube and thereby gives rise to a'restriction in the tube, but of course it is quite possible to so arrange the valve and operating means that on opening, the valve head is lowtainer'may be circular and rotatable about the vertical aXis, and may be provided with several filling points,

each with a corresponding base platform situated below it and arranged to revolve about the same axis as the bulk container, As the base platforms revolve aroundanaasoo the central of the machine they may be raised and loweredtby. avcam device and, conveniently, the filling operation may be timed to becornpleted in one revolution of themachine.

What .we claim is: I p I 1. A displacement filling apparatus comprising a filling tube, a valve for said filling tube, an air vent tube adjacent said filling tube, a'valve' at the loiver end of i said air vent 'tube, the opening through said air vent tube and air vent tube valve being large enough to permit venting of air through viscous liquid contained therein, sealing means encircling said filling and air vent tubes, said sealing means being adapted for engagement and displacement by a container mouth, means operative by initial upward displacement of said seal-' ing means to open said air vent valve, means operative by further upward displacement'of said sealing means to open said filling tube valve, and means for closing said valves before downward movement of said sealing'means is initiated. 3

2; A displacement filling apparatus comprising a filling tube, a valve for said filling tube, an air vent tube adjacent said filling tube,'a valve at the lower end ofsaid air vent tub'e, the opening through said air vent tube and air vent tube valve being large enough to permit venting of air through viscous liquid contained therein, sealing means encircling said filling and air venttubes, said sealing means being adapted for engagement and displacement by a container mouth, means operative by initial upward displacement of said sealing means to open said air vent valve, means operative by further upward displacement of said sealing means to seal the container mouth and open said filling tube valve, and' 'means for closing said valves before downward movement of said sealing means is initiated.

References Cited in the file of this patent UNITED STATES PATENTS V Namur Apr. 16, 1940 

1. A DISPLACEMENT FILLING APPARATUS COMPRISING A FILLING TUBE, A VALVE FOR SAID FILLING TUBE, AN AIR VENT TUBE ADJACENT SAID FILLING TUBE, A VALVE AT THE LOWER END OF SAID AIR VENT TUBE, THE OPENING THROUGH SAID AIR VENT TUBE AND AIR VENT TUBE VALVE BEING LARGE ENOUGH TO PERMIT VENTING OF AIR THROUGH VISCOUS LIQUID CONTAINED THEREIN, SEALING MEANS ENCIRCLING SAID FILLING AND AIR VENT TUBES, SAID SEALING MEANS BEING ADAPTED FOR ENGAGEMENT AND DISPLACEMENT BY A CONTAINER MOUTH, MEANS OPERATIVE BY INITIAL UPWARD DISPLACEMENT OF SAID SEALING MEANS TO OPEN SAID AIR VENT VALVE, MEANS OPERATIVE BY FURTHER UPWARD DISPLACEMENT OF SAID SEALING MEANS TO OPEN SAID FILLING TUBE VALVE, AND MEANS FOR CLOSING SAID VALVES BEFORE DOWNWARD MOVEMENT OF SAID SEALING MEANS IS INITIATED. 